On 16/10/2026 12:40 pm, Chen Huei Lok wrote:
Add the device tree nodes that the N5X DDR retention restore path depends
on. Reintroduce the fs-loader node and the &sdr DDR calibration backup
properties (firmware-loader, intel,ddrcal-qspi-offset and
intel,ddrcal-ddr-offset) that were dropped during the switch to the
upstream Linux DT config. These describe where the backup calibration
data is stored and the firmware-loader instance used to read it back in
SPL.
Document the intel,sdr-ctl-n5x retention properties in
doc/device-tree-bindings/ram/intel,sdr-ctl-n5x.txt, including the QSPI
calibration-restore trust model (System Manager retention bit plus flash
integrity checks) and fail-closed behaviour, and add an F: entry under
ARM ALTERA SOCFPGA in MAINTAINERS for that binding path.
Use bootph-all in place of the legacy u-boot,dm-pre-reloc so the nodes
are bound in the pre-relocation SPL phase on the migrated device tree.
Signed-off-by: Tien Fong Chee <[email protected]>
Signed-off-by: Chen Huei Lok <[email protected]>
---
MAINTAINERS | 1 +
arch/arm/dts/socfpga_n5x_socdk-u-boot.dtsi | 13 ++++++
.../ram/intel,sdr-ctl-n5x.txt | 44 +++++++++++++++++++
3 files changed, 58 insertions(+)
create mode 100644 doc/device-tree-bindings/ram/intel,sdr-ctl-n5x.txt
diff --git a/MAINTAINERS b/MAINTAINERS
index 420a3bbf730..3f83a3b11a1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -181,6 +181,7 @@ M: Simon Goldschmidt <[email protected]>
M: Tien Fong Chee <[email protected]>
S: Maintained
T: git https://git.u-boot-project.org/u-boot/custodians/u-boot-socfpga.git
+F: doc/device-tree-bindings/ram/intel,sdr-ctl-n5x.txt
N: altera
N: agilex
N: socfpga
diff --git a/arch/arm/dts/socfpga_n5x_socdk-u-boot.dtsi
b/arch/arm/dts/socfpga_n5x_socdk-u-boot.dtsi
index 3de75f36cbb..ea95d04d37d 100644
--- a/arch/arm/dts/socfpga_n5x_socdk-u-boot.dtsi
+++ b/arch/arm/dts/socfpga_n5x_socdk-u-boot.dtsi
@@ -8,6 +8,12 @@
#include "socfpga_n5x-u-boot.dtsi"
/{
+ fs_loader0: fs-loader {
+ bootph-all;
+ compatible = "u-boot,fs-loader";
+ sfconfig = <0 0>;
+ };
+
chosen {
u-boot,spl-boot-order = &mmc;
};
@@ -36,6 +42,13 @@
};
};
+&sdr {
+ intel,ddrcal-qspi-offset = "0x7000000";
+ intel,ddrcal-ddr-offset = "0x100000";
+ firmware-loader = <&fs_loader0>;
+ bootph-all;
+};
+
&flash0 {
bootph-all;
cdns,page-size = <256>;
diff --git a/doc/device-tree-bindings/ram/intel,sdr-ctl-n5x.txt
b/doc/device-tree-bindings/ram/intel,sdr-ctl-n5x.txt
new file mode 100644
index 00000000000..a86e7efdfb9
--- /dev/null
+++ b/doc/device-tree-bindings/ram/intel,sdr-ctl-n5x.txt
@@ -0,0 +1,44 @@
+* Intel N5X SDRAM controller
+
+Required properties:
+--------------------
+- compatible: must be "intel,sdr-ctl-n5x"
+
+Optional properties (DDR retention):
+------------------------------------
+- intel,ddrcal-qspi-offset: string, hex byte offset of the calibration
+ backup in QSPI (e.g. "0x7000000"). Used by SPL to load the backup
+ via the firmware loader.
+- intel,ddrcal-ddr-offset: string, hex address in DRAM where a valid
+ backup is copied after a successful restore (e.g. "0x100000").
+- firmware-loader: phandle to a "u-boot,fs-loader" node used to read
+ the QSPI backup. If omitted, the loader under /chosen is used.
+
+Trust model (QSPI calibration restore):
+---------------------------------------
+Skipping PHY recalibration after a configuration reset is gated by the
+System Manager DDR retention bit together with the reset type.
+The QSPI-sourced calibration backup is treated as untrusted until
+integrity checks pass. Restore is fail-closed: on any missing DT
+property, flash read failure, header magic mismatch, oversized
+data_len that would overflow the HPS handoff region, CRC32 mismatch
+over the calibration payload, or SHA384 mismatch over the DDR
+configuration image, U-Boot discards the backup and runs a full PHY
+calibration instead.
+
+Example:
+--------
+
+ fs_loader0: fs-loader {
+ bootph-all;
+ compatible = "u-boot,fs-loader";
+ sfconfig = <0 0>;
+ };
+
+ sdr {
+ compatible = "intel,sdr-ctl-n5x";
+ intel,ddrcal-qspi-offset = "0x7000000";
+ intel,ddrcal-ddr-offset = "0x100000";
+ firmware-loader = <&fs_loader0>;
+ bootph-all;
+ };
Reviewed-by: Tien Fong Chee <[email protected]>
Best regards,
Tien Fong
